microtest Sulphite 5

Iodometric Titration: In acid conditions, sulphite ions are oxidised by iodine. The titration endpoint is indicated by an excess of iodine causing a colour change from colourless to blue (starch indicator).

Number of Tests

50 – 80

Interferences

Strongly alkaline water samples have to be neutralised before testing. Reducing agents other than sulphite (e.g. ascorbic acid) will give positive results.

Measuring Range

The recommended measuring range is 10 to 100 mg/L (2 – 20 drops @ 5 mg/L) for 5 mL of sample volume. This range can be extended by taking a smaller or larger water sample. For a 2.5 mL sample the measuring range is 20 to 200 mg/L and for a 10 mL sample the range is 5 to 50 mg/L.

Shelf Life

2 years

Applications

Determination and monitoring of sulphite levels in food and wine as a preservative, in industrial water treatment (boiler feed water).